1. Field of the Invention
The present invention relates generally to ultrasound imaging using an ultrasound contrast agent. In particular, a system and method for ultrasound imaging of breast tissue by injecting an ultrasound contrast agent into a duct lumen of a patient""s breast to enhance the imaging of one or more ducts within a specified lobe of the breast to improve characterization of a lesion or lesions within the duct system of the specified lobe are disclosed.
2. Description of Related Art
Surgery plays an important role in the diagnosis and treatment of cancer. In the case of breast cancer, surgery comprises a critical component of medical care where early diagnosis and treatment have demonstrated a significant improvement in survival.
Currently the surgical treatment of a breast cancer does not consider anatomical boundaries within the breast. Anatomical boundaries are, however, important in considering the mechanism of cancer spread within the breast. The breast consists of 15 to 20 lobes that begin centrally beneath the nipple-areolar complex and extend in a radial pattern to the periphery of the gland. Milk is produced in numerous small lobules that connect to each main duct. Breast cancer begins in the epithelial cells of the smaller branching ducts entering the lobules. The cancerous cells may multiply and spread within the ducts of the involved lobe and/or may multiply and form a defined mass. Cancerous spread within the ducts is not appreciated by mammography unless microcalcifications are present. Extension within the ducts may also be missed on pathological examination of the specimen unless a sample slice is taken exactly at the level of the involved duct. These limitations using current methods of lumpectomy and examination of the specimen may lead to inadequate surgical treatment of the cancer.
An ultrasound examination of the internal breast anatomy as described in U.S. Pat. No. 5,709,206 to Teboul, incorporated by reference herein, can be utilized to study the lesion and its relation to the lobe in which it is contained. By using axial ductal ultrasound scanning, identification of the affected lobe, lesion size, position within the lobe, and the possibility of other lesions within the affected lobe (e.g. multifocal cancer), and/or spread within the ducts can be delineated prior to surgical treatment.
Duct systems and small lesions within the duct system may be difficult to identify due to limitations of resolution of the ultrasound machine. Thus, there is a need for an improved method for ultrasound imaging of breast tissue to better image one or more ducts within a specified lobe of the breast to improve characterization of lesion or lesions within the duct system of the specified lobe. The improved method for ultrasound imaging would ideally facilitate more accurate diagnosis and surgical excision of lesion or lesions within the duct system of the specified lobe.
A system and method for ultrasound imaging of breast tissue by injecting an ultrasound contrast agent into a duct lumen of a patient""s breast to enhance the imaging of one or more ducts within a specified lobe of the breast to improve characterization of a lesion or lesions within the duct system of the specified lobe are disclosed. It should be appreciated that the present invention can be implemented in numerous ways, including as a process, an apparatus, a system, a device, or a method. Several inventive embodiments of the present invention are described below.
In one preferred embodiment, an improved method for ultrasound imaging of breast tissue using an ultrasound contrast agent to enhance the imaging of one or more ducts within a specified lobe of the breast to improve characterization of a lesion or lesions within the duct system of the specified lobe is disclosed. The method may help determine whether removal of the lesion requires excision of part of the lobe, the entire lobe, or the entire lobe plus surrounding adjacent tissue. The ultrasound contrast agent is injected into a duct lumen by injecting through a duct orifice on a nipple and/or through a duct wall into a duct lumen. In addition, the ultrasound contrast agent is injected into the duct lumen before and/or during ultrasound imaging.
These and other features and advantages of the present invention will be presented in more detail in the following detailed description and the accompanying figures which illustrate by way of example the principles of the invention.